The present invention relates to a drain cleaning machine and, more particularly, to a drain cleaning machine having an adjustable collet chuck mechanism for engaging a drain cleaning cable.
In one type of well known portable drain cleaning machine in wide use today, a housing structure supports a coaxial arrangement of shaft components through which a drain cleaning cable, which may comprise a plurality of interconnected sectional cables, is manually fed. The housing structure includes a clutching arrangement for selectively engaging and rotating the drain cleaning cable during a drain cleaning operation. The clutching arrangement may take one of many well known forms. For example, the clutching arrangement may include radially expandable and contractable clutch elements located between and coaxial with clutch actuating components. In such an arrangement, the clutch actuating components are axially displaceable toward and away from one another to contract and expand, respectively, the clutch elements relative to the drain cleaning cable. Typically, one of the clutch actuating components is axially fixed and the other is axially displaceable toward and away from the fixed component by means of a manually operable lever arrangement. The clutch actuating components and the clutch elements are adapted to be rotated about a feed axis of the drain cleaning cable by a drive motor and a drive coupling arrangement between the motor and one of the clutch actuating components.
In use, the drain cleaning cable is manually inserted through the apparatus and into a drain to be cleaned. If the motor is operating, the clutch elements and the clutch actuating components rotate relative to the drain cleaning cable. The drain cleaning cable may be in the form of a single long piece of cable that can be manually inserted through the apparatus until an obstruction in the drain is encountered. Alternatively, the drain cleaning cable may comprise a number of smaller sections of cable that can be successively attached to one another and inserted through the apparatus until an obstruction is encountered. In either case, when an obstruction is encountered, the operating lever may then be displaced relative to the housing so as to cause the clutch elements to engage and rotate the drain cleaning cable and clear the obstruction. The operating lever may then be released to disengage the clutch from the drain cleaning cable so that the operator can feed the drain cleaning cable further into the drain.
Gallagher, et al., U.S. Pat. No. 5,657,505, describes one such prior art drain cleaning machine that includes a frame and a housing that supports a rotatable shaft. The shaft is axially displaceable by means of a lever arrangement. The shaft supports a first clutch actuating member such that the first clutch actuating member is rotatable and axially displaceable with the shaft. A second clutch actuating member coaxial with the first clutch actuating member is rotatably supported in the housing. A radially expandable and contractable collet or clutch unit is captured between the first and second clutch actuating members for engaging and disengaging the drain cleaning cable. In particular, the first and second clutch actuating members each include conical surfaces that cause the collet or clutch unit to be contracted when the first clutch actuating member is axially displaced toward the second clutch actuating member and expanded when the first clutch actuating member is axially displaced away from the second clutch actuating member. The collet or clutch unit comprises three circumferentially adjacent arcurate clutch segments, each having conically contoured axially opposite end surfaces that slideably engage the conical surfaces of the first and second clutch actuating members. The second clutch actuating member is supported so as to be axially adjustable between a maximum and a minimum spacing relative to the first clutch actuating member, thereby enabling the collet or clutch unit to accommodate drain cleaning cables having different diameters.
The present invention relates to a drain cleaning machine including a housing adapted to receive a cable along the longitudinal axis thereof and a cage member having a first end having an axial bore therethrough and a plurality of holes located radially about a circumference thereof. The holes extend through an outer wall of the cage member. The second end of the cage member is inserted within the housing such that the axial bore corresponds with the longitudinal axis. The cage member is axially displaceable along and rotatable about the longitudinal axis and is adapted to receive the cable therethrough. Also included in the machine is a plurality of jaw elements, each of the jaw elements being inserted into and displaceable within one of the holes. A cone member surrounds the first end of the cage member. The cone member is rotatable about the longitudinal axis. The cone member is adapted to engage each of the jaw elements and displace the jaw elements radially inward within the holes when the cage member is axially displaced along the longitudinal axis. A motor is coupled to the cone member for rotating the cone member, wherein rotation of the cone member causes rotation of the cage member. The jaw elements are adapted to engage and grip the cable such that rotation of the cage members causes rotation of the cable about the longitudinal axis.
The cone member may include a plurality of first engagement surfaces and a plurality of second engagement surfaces and the second engagement surfaces by rotating the cage member with respect to the cone member. In addition, each of the jaw elements may have a sloped top surface that engages corresponding ones of the first engagement surfaces when the jaw elements are aligned with the first engagement surfaces and engages corresponding ones of the second engagement surfaces when the jaw elements are aligned with the second engagement surfaces, wherein the first engagement surfaces and the second engagement surfaces have an inward cant. The first engagement surfaces may each comprise a first arcuate section forming a part of a first circular section having a first radius and the second engagement surfaces may each comprise a second arcuate section forming a part of a second circular section having a second radius. The holes may be spaced equally about the circumference of said cage member, in which case the first engagement surfaces are spaced equally about a perimeter of the cone member and the second engagement surfaces are spaced equally about the perimeter of the cone member.
In one embodiment, the top surfaces of the jaw elements engage corresponding ones of the first engagement surfaces when the jaw elements are aligned with the first engagement surfaces and engage corresponding ones of the second engagement surfaces when the jaw elements are aligned with the second engagement surfaces. In this embodiment, the jaw elements are displaced a first distance within the axial bore of the cage member when engaging the first engagement surfaces and a second distance within the axial bore of the cage member when engaging the second engagement surfaces.